In two of this summer's biggest action movies, the hero's mentor turns out to be a lying, manipulative sack of villainy. And nobody in the audience is surprised, because it's a scifi fact of life: mentors lie to you. They feed you half-truths ("Darth Vader killed your dad") and outright lies, to get you to follow their agenda. That's just what mentors do. But the good news is, studying the deceitful ways of scifi mentors can help you to deal with your misleading mentros in real life. Spoilers ahead.

Okay first of all, now that you've agreed to be spoiled: this summer's movies featuring untrustworthy mentors include Iron Man and Wanted. In Iron Man, we hear a lot of vague stuff about how Obadiah (Jeff Bridges) gave all this guidance to Tony Stark after Tony's dad died, and then of course Obadiah turns out to be a backstabbing asswipe. And in Wanted, Morgan Freeman does a huge Obi-Wan impression (but doesn't teach James McAvoy how to shop for fresh fruit) and then of course we discover his whole happy magic-loom-of-murderous-destiny story is a monstrous lie.

So here are some other great lying mentors from classic scifi, and the lessons you can learn from their mendaciousness.

So yeah, Obi-Wan: not the most honest mentor out there either. Here's what he tells Luke in the original Star Wars:

A young Jedi named Darth Vader, who was a pupil of mine until he turned to evil, helped the Empire hunt down and destroy the Jedi Knights. He betrayed and murdered your father.

Takeaway lesson: We've all had mentors who pulled shit like this. Like trying to convince you that their rivals in middle management were evil SOBs who totally wasted the office snack budget on their own "sales fiesta."

Of course, Obi Wan's a paragon of honesty compared to Palpatine, who takes young Anakin under his wing in the Star Wars prequels and feeds him all sorts of nonsense, including "the Dark Side of the Force can save your wife from death."

Ra's Al Ghul teaches Bruce Wayne how to be a stealthy head-kicking shadow of justice in Batman Begins. Which is great, until it turns out his League Of Shadows is really an evil organization that wants to destroy Gotham City for some vague reason.

Takeaway lesson: You can learn some useful skills from your mentor... even if you end up hating what the mentor wants you to use them for.

As this TV Tropes entry on Evil Mentors points out, Sylar becomes a mentor to Maya, the girl with the runniest mascara in the world. He tells her a bunch of lies about who he is and where he comes from, and also tells a lie of omission about that whole "I killed your brother thing." But mostly, he tries to influence her into using her runny-mascara powers for ebil.

Takeaway lesson: When your mentor tries to get you to go on a goo-eyed killing spree, or generally compromise your deepest principles, it may be time to find another shoulder to cry on.

Jordan Collier in The 4400 takes super-healer Shawn Farrell under his slimy wing and becomes his mentor and surrogate father... until Shawn realizes that Jordan is secretly using death-ninjas to commit terrorism against all those annoying vanilla non-superpowered people.

Thomas Nau in Vernor Vinge's A Deepness In The Sky rapes and murders Qiwi's mother in front of her. But then he erases her memory using a version of his Focusing technique, and turns her into his trusted assistant. Every now and then, she starts to remember the truth and tries to escape, but he just mindwipes her again.

Takeaway lesson: Ummm... pay attention to that little voice in the back of your head, I guess?

Arvin Sloane in Alias is the perfect nurturing, caring boss for young Sydney... until it turns out that every word that comes out of his mouth is poisonous trash. Basically, he's not one of the good guys, and he doesn't really work for the CIA, and he's not trying to bring about world peace and harmony and happy vibes.

Takeaway lesson: If your father figure has your boyfriend murdered because you got careless in your pillow talk, that could be a clue to something.

Joseph Korso takes young Cale Tucker under his wing in Titan A.E., saving his life and teaching him how to pilot a spaceship and race Wake Angels for fun and good luck and all that good stuff. But then it turns out he's secretly working for the evil alien Drej.

Takeaway lesson: If your mentor has a special knack for sneaking you aboard the evil aliens' spaceships and piloting them, it could be because he has a certain... affinity for those bastards. Just a heads up.

Elijah Price teaches David Dunn how to be a superhero in M. Night Shyamalan's Unbreakable... but then it turns out Elijah, aka Mr. Glass, is secretly a supervillain who caused several disasters, including a train wreck, to find un unbreakable hero.

Takeaway lesson: If all the pieces fall into place for your mentor to "discover" your talents, then it may not just be a coincidence.

And then there's Alan Moore's graphic novel V For Vendetta, where V lies to his acolyate Evey about a whole bunch of things... most notably he puts her into a fake, head-shaving prison camp in order to stiffen her spine for the things that must be done.

Takeaway lesson: There's hazing and then there's crazy hazing. If your mentor believes in the "prison camp" model of employee orientation - or even just paintball gone too far - it's time to bail.

I feel like Professor X from the X-Men has lied to his pupils a thousand times, but the only examples I can think of are when he secretly suppressed Jean Grey's abilities in the third X-Men movie, and when he hid the fact that he was in love with Jean Grey in Ultimate X-Men. He also spared Magneto's life but told everyone he'd killed Magneto in Ultimate X-Men as well.

Takeaway lesson: If your mentor is secretly in love with you and is secretly holding you back and sabotaging your abilities, it maybe time to get mental on your mentor.

And then there's Bill Adama in the new Battlestar Galactica, who lies to his protegee Starbuck (and everyone else) about knowing the secret location of Earth. Laura Roslin tells Starbuck the old man has been lying, which leads to this exchange between Starbuck and Adama:

"How much longer 'til we reach Earth?" "It's hard to say." "You got a guess?" "You know I don't like to guess." "We getting closer?" "I'm sure we are. Good luck on the next test."

Finally, a pissed off Starbuck decides to obey the President's orders and go back to Caprica to get the Arrow of Apollo.

Takeaway lesson: If someone blows the whistle on your lying mentor, you may as well listen to the whistleblower instead. You can't do much worse, and you might get something useful out of it.

Other mentors we almost forgot include Sally Jupiter in Watchmen, who hides her daughter's true parentage from her. And the Confessor in Astro City, a superhero who hides his vampirism from his plucky sidekick. And of course Captain Beatty in Fahrenheit 451, who pressures Guy Montag to burn all of the books in his possession, and yet quotes constantly from books himself. Who did we forget?